The present invention relates to a device for detecting developed power in exercise equipment, and comprising a rotary wheel drivable by a person taking exercise, a device for determining the speed of rotation of the wheel, a brake jaw applicable against the wheel, a mounting device with a first part which, in the direction of movement of the wheel, is fixedly secured in the exercise equipment, and a second part which, against spring action, is movable in the direction of movement of the wheel and to which the brake jaw is connected.
Exercise equipment with an ergonometer function is previously known in the art, one example of such is shown in EP 0 166 843 B1. This publication shows an ergonometer cycle, i.e. exercise equipment that measures the power of the work developed by the exercising person.
The ergonometer cycle according to EP 0 166 843 B1 has a flywheel that is driven in a rotary movement by the person using the ergonometer cycle. The cycle has a fork on which handlebars are secured which are concentric with the centre of rotation of the flywheel. Along these handlebars, an assembly with two pivotal brake jaws is displaceable and spring-biased against the direction of rotation of the flywheel. On application of the brake jaws against the peripheral surface of the flywheel, the braking force draws the assembly in the direction of rotation of the flywheel against spring force so that a displacement occurs. This displacement will be in response to the retardation force exercised on the flywheel. The greater the retardation or braking force, the greater will be this displacement.
The magnitude of the displacement is then transferred by the intermediary of a wire to a display instrument which also includes a speedometer indicating the speed of rotation of the flywheel.
In the above-described design and construction there are several different error sources. The reason for this is int. al. the considerable movement that the assembly with the brake jaws undergoes on use of the ergonometer cycle. Already minor defects in precision in the guiding that permits the movements of the assembly with the brake jaws result in loss of measurement accuracy. A further error source is the relatively great friction that may be expected in the wire which transfers the movement to the display unit. In addition, problems may occur because of wear in moving parts, insufficient lubrication thereof, etc.
It is desirable to design the device intimated by way of introduction such that the drawbacks inherent in the prior art technology are obviated. In particular, it is desirable to combine a high level of measurement accuracy with simple and economical manufacture. It is also desirable to design the device so that it operates without any major movements that may cause wear or varying geometry during operation.
In a device according to an aspect of the present invention, there is connected, to the first and second parts, a sensor for determining the movement of the second part in relation to the first in the direction of movement of the wheel.